Just because domestic dogs have developed genes that wolves do not have -

Erik Axelsson et al, 2012/13 - genes named AMY2B; MGAM; SGLT1

- which allow the dog to digest starches better (i.e. a wider range of vegetable matter, including some that humans eat but wolves never would), does not stop dogs from eating only what a wolf could. Neither does it automatically mean that the dog with that genetic evolution is better off eating increased starches. It is possible to argue that the dog has only developed this genetic difference because it gained access to human foods (adapt or die, sort of thing), and not that it would have been essential to the continuance of the 'dog' rather than the 'wolf'.

Bear in mind also that, physically rather than genetically, there is still almost no difference to the entire digestive tract, mouth to anus, between the dog and the wolf. The most notable difference is that the wolf retains a stronger jaw and bigger teeth, which of course if you are the one bringing down your live raw meals, would be logically necessary. [ I don't think that matters much where the prey is mice or ground squirrels or chicken.]